app keeps crashing

[bugsbunny88]

Hello if I could kindly get some support.
Been using the app for almost a year without an issue but recently it just keeps crashing.
By removing files and putting them back in I've traced it down to the Calendars folder.

within the calendars folder I have 3 folders with: colID12345 (the 12345 are 3 different numbers)
I then have 2 folders with long alpha numeric code; ie. 32fdabc2-f7bf.... etc...

Now when I leave the long alpha-num folders ; decsyncCC from F-Droid; doesn't see any calendars...
and then I add the colID's it just crashes.
I'm really confused how to troubleshoot beyond this point

[bugsbunny88]

Ok I was able to get the app and calendar semi-working by deleting files. I assumed the app crashed because of sync errors. But I'm afraid its going to happen again. From my understanding the long alpha numeric code 32fdabc2-f7bf.... etc... was some old app work and can safely be deleted.

so I just kept the coldID's

however I'm afraid the sync errors will happen again and I'm confused at the inner workings if I could get an explanation. Whats happening inside all of them ie. calendars/coldIDxxxx/info :

I have 4 folders already....
Pixel3a-DecsyncCC-12345
Pixel3a-DecsyncCC-67891
bugsbunny-Evolution-92817
bugsbunny-Evolution-93716

What is the meaning of this? I am using Syncthing folder connected to 1 laptop and 1 phone. Obviously Evolution instance being my laptop ; 2 different folders. and Pixel my phone , 2 different folders... why isn't it all in 1 folder?